Usefulness of Spoligotyping in Molecular Epidemiology of Mycobacterium bovis -Related Infections in South America

Abstract

Two hundred twenty-four Mycobacterium bovis isolates, mainly from South American countries, were typed by spoligotyping, and 41 different spoligotypes were identified. A total of 202 M. bovis isolates (90%) were grouped into 19 different clusters. The largest cluster contained 96 isolates (42.8%) on the basis of the most frequently observed spoligotype, spoligotype 34. Nineteen M. bovis isolates from humans in Argentina had spoligotypes and polymorphic GC-rich repetitive sequence (PGRS) types that represented the most common types found among isolates from cattle. All five isolates from Uruguay and three of the six isolates from Paraguay had spoligotypes that were also detected for isolates from Argentina. The spoligotypes of isolates from Brazil, Costa Rica, and Mexico and of some of the isolates from Paraguay could not be found in Argentina. A total of 154 M. bovis isolates were selected in order to compare the discriminative power of spoligotyping and restriction fragment length polymorphism (RFLP) analysis with direct repeat (DR) and PGRS probes. By spoligotyping, 31 different types were found, whileAluI-digested DR probe-associated RFLP analysis identified 42 types, and RFLP analysis with the PGRS probe also detected 42 types; these were partly independent of the DR types. By combining the results obtained by spoligotyping and by RFLP analysis with the DR and PGRS probes, 88 different types were obtained. Although the differentiation of M. bovis by spoligotyping was less discriminatory than differentiation by RFLP analysis with the DR and PGRS probes, spoligotyping is easier to perform and its results are easier to interpret. Therefore, for the purpose of typing of M. bovisisolates, spoligotyping could be performed first and the isolates could be grouped into clusters and then analyzed by RFLP analysis with the DR and PGRS probes.

Individual Animals of a Cattle Herd Infected with the Same Mycobacterium bovis Genotype Shows Important Variations in Bacteriological, Histopathological and Immune Response Parameters

“…As all the isolates share the same spoligotype, a common source of infection is suggested. Strains with this spoligotype were not previously detected in Argentina and Brazil (Zumárraga et al, 1999). At present it is not possible to determine if this strain is more virulent or if it spreads in that local region without the competence of others.…”

Molecular Typing of Mycobacterium bovis Isolates in Argentina: First Description of a Person-to-Person Transmission Case

“…The nine M. bovis samples from different provinces of Argentina had five different spoligotypes (Table 2). The main type observed, arbitrarily designed spoligotype 34, was also the most frequently found in cattle (Zumárraga et al., 1999); (Fig. 2).…”

“…The other spoligotypes grouped in clusters were spoligotypes 3 and 4 (Fig. 2); these are sporadically found in cattle (Zumárraga et al., 1999). Variable number tandem repeat analysis of the nine M. bovis isolated from humans identified five different patterns.…”

“…In order to determine which samples showing the M. tuberculosis complex PRA restriction profiles corresponded to M. bovis , a multiplex PCR was designed. This strategy is based on the amplification of the 12.7‐kb genomic region previously characterized in our laboratory (Zumárraga et al., 1999) (Fig. 1).…”

“…Before M. bovis sequence was available, Zumárraga et al. demonstrated that M. bovis and M. bovis BCG lack a 12.7‐kb fragment present in the genome of M. tuberculosis (Zumárraga et al., 1999). This region was used to differentiate M. tuberculosis from M. bovis and was later identified as RD7 by Brosch.…”